rs779336305

Variant names:

• chr2-38986048-G-C
• rs779336305
• NM_005633.4:c.3778C>G

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_Moderate BS2

The NM_005633.4(SOS1):​c.3778C>G​(p.Pro1260Ala) variant causes a missense change. The variant allele was found at a frequency of 0.00000958 in 1,461,718 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000096 (0 hom.)
• Consequence: SOS1 NM_005633.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 4.33

Genes affected

SOS1 (HGNC:11187): (SOS Ras/Rac guanine nucleotide exchange factor 1) This gene encodes a protein that is a guanine nucleotide exchange factor for RAS proteins, membrane proteins that bind guanine nucleotides and participate in signal transduction pathways. GTP binding activates and GTP hydrolysis inactivates RAS proteins. The product of this gene may regulate RAS proteins by facilitating the exchange of GTP for GDP. Mutations in this gene are associated with gingival fibromatosis 1 and Noonan syndrome type 4. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.1308263).
• BS2: High AC in GnomAdExome4 at 14 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SOS1	NM_005633.4	c.3778C>G	p.Pro1260Ala	missense_variant	Exon 23 of 23	ENST00000402219.8	NP_005624.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SOS1	ENST00000402219.8	c.3778C>G	p.Pro1260Ala	missense_variant	Exon 23 of 23	1	NM_005633.4	ENSP00000384675.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251108 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135690

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000958 AC: 14 AN: 1461718 Hom.: 0 Cov.: 32 AF XY: 0.0000151 AC XY: 11 AN XY: 727152

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000126

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000936 Hom.: 0

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.0000546

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Noonan syndrome 4 Uncertain:1

-

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Cardiovascular phenotype Uncertain:1

Nov 09, 2021

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.P1260A variant (also known as c.3778C>G), located in coding exon 23 of the SOS1 gene, results from a C to G substitution at nucleotide position 3778. The proline at codon 1260 is replaced by alanine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Fibromatosis, gingival, 1 Uncertain:1

-

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

RASopathy Uncertain:1

May 29, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 1260 of the SOS1 protein (p.Pro1260Ala). This variant is present in population databases (rs779336305, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with SOS1-related conditions. ClinVar contains an entry for this variant (Variation ID: 477723). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on SOS1 protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.068
BayesDel_addAF	Uncertain	0.028	T
BayesDel_noAF	Benign	-0.20
CADD	Benign	23
DANN	Benign	0.88
DEOGEN2	Benign	0.40	T;T;T
Eigen	Benign	-0.059
Eigen_PC	Benign	0.039
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Benign	0.80	.;T;T
M_CAP	Benign	0.044	D
MetaRNN	Benign	0.13	T;T;T
MetaSVM	Benign	-0.41	T
MutationAssessor	Uncertain	2.0	M;M;.
PrimateAI	Uncertain	0.69	T
PROVEAN	Benign	-0.52	N;N;N
REVEL	Uncertain	0.34
Sift	Benign	1.0	T;T;T
Sift4G	Benign	0.095	T;T;T
Polyphen		0.13	B;B;.
Vest4		0.27
MutPred		0.25		Loss of glycosylation at P1260 (P = 8e-04);Loss of glycosylation at P1260 (P = 8e-04);.;
MVP		0.42
MPC		0.22
ClinPred		0.15	T
GERP RS		5.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.2
Varity_R		0.11
gMVP		0.18

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs779336305; hg19: chr2-39213189;